CN103955623B - External network measuring and sampling error correction method based on prediction and correction algorithm - Google Patents

External network measuring and sampling error correction method based on prediction and correction algorithm Download PDF

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CN103955623B
CN103955623B CN201410206710.XA CN201410206710A CN103955623B CN 103955623 B CN103955623 B CN 103955623B CN 201410206710 A CN201410206710 A CN 201410206710A CN 103955623 B CN103955623 B CN 103955623B
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CN103955623A (en
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张海波
李鹏华
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North China Electric Power University
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North China Electric Power University
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Abstract

The invention discloses an external network measuring and sampling error correction method based on prediction and correction algorithm and belongs to the technical field of operation and control of electric power systems. The method comprises the following steps: after the starting of distributed state estimation calculating, a main subsystem and a slave subsystem are respectively used for acquiring parameters used for computing and measuring section time differences; the slave subsystem is used for sending the acquired parameters used for computing and measuring the section time differences to the main subsystem; the main subsystem is used for computing and measuring the section time differences and sending the measured section time differences to the slave subsystem; the slave subsystem is used for correcting the measured values of all measured points according to the measured section time differences.The external network measuring and sampling error correction method provided by the invention is applied before distributed state estimation calculation, and is used for adjusting measured data of all control centers, participating in calculation, so as to reduce estimation differences of a boundary region. Therefore, all original measuring information, participating in distributed state estimation calculation, of the boundary region of the subsystem are enabled to be consistent basically, the consistency of intranet measuring information of all subsystems and the local measuring information of a calculation initiating system is ensured, and the calculation accuracy is improved.

Description

Sampling error modification method is measured based on the outer net estimated with correcting algorithm
Technical field
The invention belongs to the operation of power system and control technology field, more particularly, to a kind of being based on are estimated and correcting algorithm Outer net measure sampling error modification method.
Background technology
At present, one of trend of power system development is exactly Power System Interconnection, and in addition the access of the new forms of energy such as large-scale wind power is right The impact of network trend and dynamic characteristic is extended to network-wide basis, objectively requires electrical network correlation All Control Center (system) to pass through Interacted system state estimation sets up the unified online computation model of the whole network.In actual motion, each control centre is only responsible for supervision The network of oneself affiliated area, is each entered by the real time data that SCADA system obtains local power grid operation according to some cycles Row state estimation calculates.Because All Control Center state estimation obtains, the data moment is inconsistent each other, dividing between control centre When cloth state estimation calculates, the time difference is had using the metric data from different control centres, this will bring outer net to estimate Error, the accuracy of impact state estimation.Because the measurement sampled data from SCADA does not have time scale information, lead to from not The time difference with the measuring section of control centre is difficult to direct access, thus cannot be directly according to the measuring section time difference external network data It is modified.
Often there is greater overlap modeling region, using the overlapping modeling of different control centres between actual electric network control centre Identical measuring point difference this feature of measuring value in region, measures change curve according to each measuring point in overlay region, estimates out two systems real The border section time difference, other adjacent subsystems were corrected to metric data according to the section time difference, made the institute of participation Distributed Calculation The measuring section having control centre is under synchronization, improves the accuracy that distributions are estimated.
Document 1 (Zhao Hongga, Xue Yusheng, Gao Xiang, Pan Yongwei, Cen Zonghao, Li Bijun.《The delay inequality of measurement is estimated to state The impact of meter and its countermeasure [J]》. Automation of Electric Systems, 2004,21:Measurement transmission delay is analyzed to state estimation in 12-16) The impact of precision, and be uniformly distributed model and propose processing method according to metric data time delay.But the method inapplicable forwarding The data of data and direct collection the situation deposited.
For measurement transmission delay problem, document 2 (Leou, R.C., Lu, C.N.Adjustment of the External Network's Measurements and its Effect on the Power Mismatch.Thirty-Forth IAS Annual Meeting [C] .1999,102 (3):2072-2076) propose two kinds of new forecast models and improve degree of accuracy, respectively It is winters season autoregression model and ARMA model, but the computational accuracy of the method is difficult to ensure that.
Document 3 (SU C L, LU C N.Interconnected network state estimation using Randomly delayed measurement s.IEEE Trans on Power Systems, 2001,16 (4): 8702878) suppose that metric data follows specific distribution, and propose Stochastic propagation Kalman filtering algorithm to ask solving time delay Topic, but the calculating of this algorithm is complicated.
Document 4 (show consideration for, Chen Genjun, Chen Songlin, Li Jiuhu, Tang Guoqing, Yu Erkeng.《Metric data time difference compensation state is estimated Meter method [J]》. Automation of Electric Systems, 2009,08:Time delay according to different measurements in 44-47), introduces the corresponding time difference Compensating factor, revises the measurement of time delay using the metric data variable quantity of continuous two data section and the time difference compensation factor, Measure delay problem to process.The method does not provide the concrete grammar asking for section time delay, but think measurement transmission delay it is known that And it is translated into compensating factor, introduce state estimation and measure equation.
Content of the invention
It is an object of the invention to, provide and a kind of measure sampling error correction side with the outer net of correcting algorithm based on estimating Method, using identical measuring point difference this feature of measuring value in different control centres overlapping modeling region, according to each measuring point in overlay region Measure change curve, estimated out for the two system actual profile time differences, master subsystem again the section estimated out the time difference be sent to adjacent Other subsystems, other subsystems are corrected to metric data according to the section time difference, make participation distributions estimate meter The measuring section of all control centres calculated is under synchronization, improves the accuracy that distributions are estimated.
To achieve these goals, technical scheme proposed by the present invention is, a kind of based on the outer net estimated with correcting algorithm Measure sampling error modification method, it is characterized in that methods described includes:
Step 1:Distributions estimate calculate start after, master subsystem and from subsystem obtain respectively for calculate measure The parameter of the section time difference;
Described master subsystem is the subsystem initiating to calculate;
Step 2:From subsystem, being used for of obtaining is calculated the parameter of the measuring section time difference and send to master subsystem;
Step 3:The master subsystem computation and measurement section time difference simultaneously sends the described Measure section time difference to from subsystem;
Step 4:From subsystem, the measuring value of each measuring point is revised according to the measuring section time difference.
Described master subsystem obtains and includes for the parameter calculating the measuring section time difference:Master subsystem stores according to itself The historical metrology section of overlapping region, extracts the measuring value in each measuring point nearest 1 cycle, is designated as the first measuring value Si,1;Ask for each Measuring point first measures the slope K of change near lineari,1, each measuring point second measure the slope K of change near lineari,2With each measuring point Projection vertical coordinate S on the first regression straight linei,1Y
Wherein, i=1,2 ..., n, n are the measuring point number of overlapping region;
The described slope K asking for each measuring point first measurement change near lineari,1Including following sub-step:
Sub-step A1:Master subsystem extracts the nearest p of each measuring point from the historical metrology section of the overlapping region that itself stores The measuring value in individual cycle;Wherein, p is setting value;
Sub-step A2:Measuring value using each measuring point nearest p cycle predicts the measuring value of each measuring point next cycle;
Sub-step A3:Measuring value by the measuring value in nearest for each measuring point 1 cycle and each measuring point next cycle of prediction It is connected, obtain each measuring point first and measure change near linear;
Sub-step A4:Calculate the slope K that each measuring point first measures change near lineari,1.
The described slope K asking for each measuring point second measurement change near lineari,2Including following sub-step:
Sub-step B1:Master subsystem extracts each measuring point nearest 2 from the historical metrology section of the overlapping region that itself stores The measuring value in individual cycle;
Sub-step B2:The measuring value in nearest for each measuring point 2 cycles is connected, obtains each measuring point second measurement change approximately straight Line;
Sub-step B3:Calculate the slope K that each measuring point second measures change near lineari,2.
Described ask for projection vertical coordinate S on the first regression straight line for each measuring pointi,1YIncluding following sub-step:
Sub-step C1:Nearest p of each measuring point of historical metrology profile extraction of the overlapping region that master subsystem stores from itself The measuring value in cycle;Wherein, p is setting value;
Sub-step C2:According to the measuring value in each measuring point nearest p cycle, calculate the first regression straight line of each measuring point;
Sub-step C3:The measuring value in nearest for each measuring point 1 cycle is projected on the first regression straight line of this measuring point;
Sub-step C4:Calculate the vertical coordinate S of subpointi,1Y.
Described acquisition from subsystem includes for the parameter calculating the measuring section time difference, is stored according to itself from subsystem The historical metrology section of overlapping region, extracts the measuring value of the nearest a cycle of each measuring point, is designated as the second measuring value Si,2;Ask for Projection vertical coordinate S on the second regression straight line for each measuring pointi,2Y
Wherein, i=1,2 ..., n, n are the measuring point number of overlapping region.
Described ask for projection vertical coordinate S on the second regression straight line for each measuring pointi,2YIncluding following sub-step:
Sub-step D1:Extract the measurement in each measuring point nearest p cycle the historical metrology section of overlapping region from subsystem Value;Wherein, p is setting value;
Sub-step D2:According to the measuring value in each measuring point nearest p cycle extracted, the second recurrence calculating each measuring point is straight Line;
Sub-step D3:The measuring value in nearest for each measuring point 1 cycle is projected on the second regression straight line of this measuring point;
Sub-step D4:Calculate the vertical coordinate S of subpointi,2Y.
The described time difference calculating each measuring point specifically includes following sub-step:
Sub-step E1:Make i=1, N1=0, N2=0;
Sub-step E2:When measuring point i meets Ki,2>0 and Si,2Y<Si,1Y, or Ki,2<0 and Si,2Y>Si,1YWhen, then make N1=N1+ 1;
When measuring point i meets Ki,2<0 and Si,2Y<Si,1Y, or Ki,2>0 and Si,2Y>Si,1YWhen, then make N2=N2+1;
Sub-step E3:If i >=n, execute sub-step E4;Otherwise, make i=i+1, return sub-step E2;
Sub-step E4:If N1≥N2, then according to formula Δ tj=(Sj,1-Sj,2)/Kj,2Calculate the time difference of measuring point j;If N1<N2, then according to formula Δ tj=(Sj,1-Sj,2)/Kj,1Calculate the time difference of measuring point j;
Wherein, j=1,2 ..., n, n are the measuring point number of overlapping region.
The computing formula of the described measuring section time difference isWherein, n is the measuring point number of overlapping region.
Described step 4 includes following sub-step:
Sub-step F1:From subsystem, change curve is measured according to each measuring point of subsystem historical metrology cross section correct, specially:
As Δ T12The measuring value in each measuring point of historical metrology profile extraction nearest q cycle, root when >=0, is utilized from subsystem Predict the measuring value of each measuring point next cycle according to the measuring value extracting, further according to the measuring value in each measuring point nearest q-1 cycle With the measuring value of each measuring point next cycle of prediction, matching obtains each measuring point and measures change curve f (t);
As Δ T12<The measuring value in each measuring point of historical metrology profile extraction nearest q cycle when 0, is utilized from subsystem, according to The measuring value in each measuring point nearest q cycle, matching obtains each measuring point and measures change curve f (t);
Wherein, q is setting value, and t is to measure the moment;
Sub-step F2:Using formulaRevise the measuring value from subsystem each measuring point i;
For revise after from the measuring section of subsystem measuring point i measuring value;
I=1,2 ..., m, m are the measuring point number of the measuring section from subsystem.
Before the present invention is applied to distributions estimation calculating, to the outer net All Control Center (subsystem) participating in calculating Metric data carry out integrated regulation, to reduce the estimation difference of borderline region so that all participation distributions estimate The subsystem borderline region initial measurement information calculating is basically identical it is ensured that each subsystem Intranet measurement information is calculated with initiation The concordance of the local measurement information of system, improves the accuracy of calculating.
Brief description
Fig. 1 is systematic sampling time difference map;
Fig. 2 is subsystem overlapping region schematic diagram;
Fig. 3 is to measure sampling error modification method flow chart based on the outer net estimated with correcting algorithm;
Fig. 4 is that each measuring point first measures change near linear generation schematic diagram;
Fig. 5 is that each measuring point second measures change near linear generation schematic diagram;
Fig. 6 is emulation platform schematic diagram;
Fig. 7 is example error analyses table;
Fig. 8 is application condition curve chart.
Specific embodiment
Below in conjunction with the accompanying drawings, preferred embodiment is elaborated.It is emphasized that the description below is merely exemplary , rather than in order to limit the scope of the present invention and its application.
For easy analysis, the present embodiment taking two subsystems (subsystem 1, subsystem 2) interconnection as a example illustrates.Assume Subsystem 1 is the master subsystem initiating Distributed Calculation, and the respective state estimation of two subsystemses participating in Distributed Calculation calculates Cycle is consistent, is Δ h.Measuring section is to participate in the measuring value of each measuring point that the subsystem of Distributed Calculation obtains in specific period Set.All measuring point sampling instants in same section are consistent, and system communication cycle is shorter, measure variation tendency consistent, often Corresponding 1 collection moment in individual cycle.
Often there is between actual electric network control centre greater overlap modeling region, the measurement calculating each measuring point in overlay region is poor Value, if measuring mean difference in allowed band, is not required to carry out Predictor Corrector.Due to system communication cycle shorter it is assumed that amount Survey variation tendency consistent, at short notice, connect the secant being formed using 2 points and to measure change curve in the approximate cycle.With All measuring point sampling instants in one section are consistent, and system communication cycle is shorter, measure variation tendency consistent.Two System History amounts Survey and carry out linear regression analyses respectively, made regression straight line is approximately consistent.
Fig. 1 is systematic sampling time difference map.As shown in figure 1, transverse axis is time shafts, after representing that each subsystem obtains electric network data Periodically carry out the moment of state estimation, the longitudinal axis represents subsystems.In Fig. 1, moment t1 (i) and its measuring section before Represent the Historic Section being stored in data base, the measuring section of moment t2 (j+1) and t1 (i+1) represents the section not gathered.And Interval [t1 (i), t2 (j+1)] with I express time, II represents interval [t2 (j+1), t1 (i+1)].M21Represent subsystem 2 in t2 (j-2) measuring section in moment.
With subsystem 1 for the system initiating calculating, i.e. master subsystem.In fig. 2, overlay region D is that master subsystem state is estimated Meter computation model and the region intersected from subsystem state estimation computation model.A measuring point M is arbitrarily taken in the D of overlay regiond, note survey Point MdIn M1Measuring value in section is S1, and note measuring value S1 measures regression straight line (the first regression straight line) upslide in master subsystem The vertical coordinate of shadow is Sd1Y, wherein M1Refer to master subsystem to initiate to calculate the calculating section being.Note measuring point MdIn section M2In measurement It is worth for S2, remember that measuring value S2 is S measuring the vertical coordinate of the upper projection of regression straight line (second regression straight line) from subsystemd2Y, remember Δ Sd=S1-S2, wherein M2Be from subsystem master subsystem initiate calculate after, be sent to the measuring section of master subsystem.From son In system, B area arbitrarily takes a measuring point Mb, remember measuring point MbIn M2Middle measuring value is Sb.
After initiating to calculate, master subsystem 1 obtains section M2Afterwards, bad data, the amount in the measuring section that will obtain are rejected Measured value carries out preliminary process, by irrational data deletion without.Bad data includes:Do not meet the measurement of Kirchhoff's law Value, measures the irrational measuring value of Sudden Changing Rate, and generator active power exceedes measuring value of its rated power etc..Reject bad data Afterwards, master subsystem 1 calculates all measuring points in overlay region in M1And M2In measurement difference, if measure mean difference in allowed band, Then it is not required to carry out Predictor Corrector, algorithm flow chart is as shown in Figure 3.
In Fig. 3, the method that the present invention provides includes:
Step 1:After distributions are estimated to calculate startup, master subsystem (is not fixing, refers to start the subsystem calculating System) and the parameter for calculating the measuring section time difference is obtained respectively from subsystem.
After master subsystem initiates to calculate, obtain the parameter for calculating the measuring section time difference.Including:Master subsystem is according to certainly The historical metrology section of the overlapping region of body storage, extracts the measuring value in each measuring point nearest 1 cycle, is designated as the first measuring value Si,1.Ask for the slope K that each measuring point first measures change near lineari,1, each measuring point second measure the slope of change near linear Ki,2With projection vertical coordinate S on the first regression straight line for each measuring pointi,1Y.Wherein, i=1,2 ..., n, n are the survey of overlapping region Point number.
Because historical metrology section includes the measuring section in each cycle, i.e. the measuring value of each each measuring point of cycle, meter Calculate after initiating, the measuring value of the nearest a cycle in the Historic Section of sampling is designated as the first measuring value S by master subsystemi,1.
Each measuring point first is measured to the slope K of change near lineari,1, its acquisition process is as follows:
Sub-step A1:The each measuring point of historical metrology profile extraction of the overlapping region that master subsystem stores from itself nearest 4 The measuring value in individual cycle.The present embodiment takes setting value p=4, and the value of p can not be too little, too little can affect prediction effect.
Sub-step A2:Measuring value using 4 nearest cycles of each measuring point predicts the measuring value of each measuring point next cycle.
Used for reference in the present invention winters forecast model, exponential smoothing forecast model, linear extrapolation forecast model, Several ultra-short term bus load Forecasting Methodology such as gray forecast approach forecast model and load variations value model, is predicted respectively.
Wherein, winters forecast model isFor the predictive value of moment n+j,For The measurement meansigma methodss of moment n,For the smoothing factor of moment n,Season sex factor for moment n+j.In the present embodiment, j =4.
Other Forecasting Methodologies are any techniques commonly known, are not the emphasis of present invention protection, therefore in the present invention no longer Repeat.
Corresponding for each Forecasting Methodology predicting the outcome is designated as X respectively1、X2、X3、X4And X5.In order to improve precision of prediction, comprehensive Conjunction employs above several method and is finally predicted the outcome.According to the prediction accuracy of various methods, predict the outcome point for it Join different weights omegai, weight determines that formula is:
min W ( Z = W T HW ) e T W = 1 - - - ( 1 )
Wherein, W=[ω12345], e=[1,1,1,1,1]T.H is 5 × 5 matrixes, is to be divided with 5 kinds of methods Yu Ce not covariance matrix between gained measuring point predictive value and measuring point actual value.With measuring point MdAs a example, various methods are tried to achieve Predictive value is assumed to be respectively:X1d、X2d、X3d、X4dAnd X5d, try to achieve weight and be followed successively by ω1d, ω2d, ω3d, ω4dAnd ω5d, then measuring point MdFinal predictive value:
Xd1dX1d2dX2d3dX4d4dX4d5dX5d(2)
Sub-step A3:Measuring value by the measuring value in nearest for each measuring point 1 cycle and each measuring point next cycle of prediction It is connected, the straight line obtaining is used for each measuring point in approximate principal and subordinate's two subsystemses overlapping region and measures change curve, this straight line is each measuring point First measures change near linear.
For any one measuring point, the measuring value in nearest 1 cycle is Si,1, the measuring value of prediction is Xi,d, by this two Value is connected, and obtains straight line, this straight line is measured change near linear as this measuring point first.As shown in figure 4, measuring point Md's First measurement change near linear is S1d=K1×t+b1.
Sub-step A4:Calculate the slope K that each measuring point first measures change near lineari,1.Due on straight line 2 points it is known that It is respectively Si,1And Xi.d, therefore straight slope Ki,1Can try to achieve.
Each measuring point second is measured to the slope K of change near lineari,2, its acquisition process is as follows:
Sub-step B1:The each measuring point of historical metrology profile extraction of the overlapping region that master subsystem stores from itself nearest 2 The measuring value in individual cycle.
Sub-step B2:The measuring value in 2 nearest for each measuring point cycles is connected, the straight line obtaining is used for approximate principal and subordinate two The each measuring point in system overlapping region measures change curve, and this straight line is that each measuring point second measures change near linear.
For any one measuring point, the measuring value in nearest 1 cycle is Si,1, the measuring value in the 2nd nearest cycle is Si,0.This two measuring values are connected, obtain straight line, this straight line is measured change near linear as this measuring point second.As Shown in Fig. 5, measuring point MdSecond measurement change near linear be S2d=K2×t+b2.
Sub-step B3:Calculate the slope K that each measuring point second measures change near lineari,2.Due on straight line 2 points it is known that It is respectively Si,1And Si,0, therefore straight slope Ki,2Can try to achieve.
For projection vertical coordinate S on the first regression straight line for each measuring pointi,1Y, it is as follows that it asks for process:
Sub-step C1:Nearest 4 of each measuring point of historical metrology profile extraction of the overlapping region that master subsystem stores from itself The measuring value in cycle.
Sub-step C2:According to the measuring value in each measuring point nearest 4 cycles, calculate the first regression straight line of each measuring point.
Because each measuring point has 4 measuring values (there is a measuring value in each cycle in 4 cycles), therefore can be according to this 4 measuring values, in conjunction with linear regression equation, are calculated the regression straight line of this measuring point, as the first recurrence of this measuring point Straight line.
Sub-step C3:The measuring value in nearest for each measuring point 1 cycle is projected on the first regression straight line of this measuring point.
Sub-step C4:Calculate the vertical coordinate S of subpointi,1Y.As calculated measuring point MdMeasuring value S1 is in its first regression straight line On projection vertical coordinate be Sd1Y.
After master subsystem initiates to calculate, obtain the parameter for calculating the measuring section time difference from subsystem.Including from subsystem The historical metrology section of the overlapping region according to itself storage for the system, extracts the measuring value of the nearest a cycle of each measuring point, is designated as the Two measuring value Si,2;Ask for projection vertical coordinate S on the second regression straight line for each measuring pointi,2Y.Wherein, i=1,2 ..., n, n are The measuring point number of overlapping region.
Because historical metrology section includes the measuring section in each cycle, i.e. the measuring value of each each measuring point of cycle.Main After subsystem initiates to calculate, the measuring value of the nearest a cycle of each measuring point can be extracted from subsystem, be designated as the second amount Measured value Si,2.
Ask for projection vertical coordinate S on the second regression straight line for each measuring point from subsystemi,2YConcrete acquisition process as follows:
Sub-step D1:Extract the measurement in each measuring point nearest 4 cycles the historical metrology section of overlapping region from subsystem Value.
Sub-step D2:According to the measuring value in each measuring point nearest 4 cycles extracted, the second recurrence calculating each measuring point is straight Line.
The measuring value in each 4 cycles of measuring point obtains from subsystem, and because each measuring point has 4 measuring values, because This can be calculated another regression straight line of this measuring point according to this 4 measuring values, as the second recurrence of this measuring point Straight line.
Sub-step D3:The measuring value in nearest for each measuring point 1 cycle is projected on the second regression straight line of this measuring point.
Sub-step D4:Calculate the vertical coordinate S of subpointi,2Y.As calculated measuring point MdMeasuring value S2 in its second regression line The vertical coordinate S of projection on straight lined2Y.
Step 2:From subsystem, being used for of obtaining is calculated the parameter of the measuring section time difference and send to master subsystem.In this step In rapid, from subsystem by the second measuring value Si,2Vertical coordinate S with subpointi,2YSend to master subsystem.
Step 3:The master subsystem computation and measurement section time difference simultaneously sends the described Measure section time difference to from subsystem.
Master subsystem is according to each measuring point the first measuring value Si,1, each measuring point the second measuring value Si,2, each measuring point first measures and becomes Change the slope K of near lineari,1, each measuring point second measure the slope K of change near lineari,2, each measuring point is in the first regression straight line On projection vertical coordinate Si,1YWith projection vertical coordinate S on the second regression straight line for each measuring pointi,2Y, calculate the time difference of each measuring point, tool Body includes:
Sub-step E1:Make i=1, N1=0, N2=0.
Sub-step E2:When measuring point i meets Ki,2>0 and Si,2Y<Si,1Y, or Ki,2<0 and Si,2Y>Si,1YWhen, then make N1=N1+ 1.
When measuring point i meets Ki,2<0 and Si,2Y<Si,1Y, or Ki,2>0 and Si,2Y>Si,1YWhen, then make N2=N2+1.
Sub-step E3:If i >=n, execute sub-step E4;Otherwise, make i=i+1, return sub-step E2;
Sub-step E4:If N1≥N2, then according to formula Δ tj=(Sj,1-Sj,2)/Kj,2Calculate the time difference of measuring point j;If N1<N2, then according to formula Δ tj=(Sj,1-Sj,2)/Kj,1Calculate the time difference of measuring point j, j=1,2 ..., n, n are overlapping region Measuring point number.
Then, the time difference according to each measuring point, calculate the measuring section time difference.Its computing formula isWherein, n For measuring point number in measuring section.
Finally, master subsystem is by Δ T12Send to from subsystem.
Step 4:From subsystem, the measuring value of each measuring point is revised according to the measuring section time difference.Revise the measuring value bag of each measuring point Include:
Sub-step F1:From subsystem, change curve is measured according to each measuring point of subsystem historical metrology cross section correct, specifically side Formula is as follows:
As Δ T12The measuring value in each measuring point of historical metrology profile extraction nearest q cycle, root when >=0, is utilized from subsystem Predict the measuring value of each measuring point next cycle, the Forecasting Methodology that the method for prediction and sub-step A2 provide according to the measuring value extracting Identical.After obtaining the measuring value of each measuring point next cycle, the measuring value using each measuring point nearest q-1 cycle is each with predict The measuring value of measuring point next cycle, matching obtains each measuring point and measures change curve f (t).Wherein, q is setting value, and t is measuring point The collection moment of measuring value.
As shown in figure 1, setting q=4, that is, extract the measuring value in each measuring point nearest 4 cycles.As Δ T12When >=0, boss is System 1 sampling is ahead of from subsystem 2, now section M24Do not gather, utilize measuring section M from subsystem 220、M21、M22And M23In advance Survey M24Middle measuring point MbMeasuring value.After predicting new value, using measuring section M21、M22、M23And M24Middle measuring point MbMeasuring value, Using newton differential technique, matching obtains each measuring point and measures change curve fb(t).Newton differential technique fitting formula is as follows:
F (x)=Pn(x)+Rn(x)
Pn(x)=f (x0)+f[x0,x1](x-x0)+f[x0,x1,x2](x-x0)(x-x1)+... (3)
+f[x0,x1,...,xn](x-x0)...(x-xn-1)
In formula (2),
Rn(x)=f (x)-Pn(x)=f [x0,x1,...,xnn+1(x)
f [ x 0 , x 1 , . . . , x k ] = f [ x 0 , . . . x k - 2 , x k ] - f [ x 0 , x 1 , . . . , x k - 1 ] x k - x k - 1 - - - ( 4 )
In formula (3), ωn+1(x)=(x-x0)(x-x1)(x-x2)...(x-xn).
As Δ T12<The measuring value in each measuring point of historical metrology profile extraction nearest q cycle when 0, is utilized from subsystem, according to The measuring value in each measuring point nearest q cycle, matching obtains each measuring point and measures change curve f (t).
In Fig. 1, it is ahead of master subsystem 1 from subsystem 2 sampling, using the existing historical metrology section M of subsystem 221、M22、 M23And M24Middle measuring point MbMeasuring value, according to newton differential technique, matching measures change curve fb(t).
Sub-step F2:Using formulaRevise the measuring value from subsystem each measuring point i.After revising The measuring value of measuring point i from the measuring section of subsystem, i=1,2 ..., m, m are the measuring point of the measuring section from subsystem Number.
Embodiment 2
The present invention passes through experiment simulation platform shown in Fig. 6, builds Bulk power system simulation model, simultaneously in EMS on RTDS (OPEN-3000) set up the physical device model consistent with RTDS phantom in.Illiteracy west electricity by stable operation on RTDS Pessimistic concurrency control, is split as the electrical network in two regions having overlap, models respectively in EMS system.Passing through wide area network simulator again will The interconnection of two simulation control centers EMS, simulates different control centres and obtains data moment nonsynchronous state, thus simulation with In actual electric network, consistent experimental situation is run at intarconnected cotrol center.The present invention set each system state estimation calculating cycle as 30s, the test data actual profile time difference of use is 20s, initiates to calculate with EMS1.
1) estimate part
A) utilize overlay region historical metrology section in EMS1 to predict new measuring section, seek each measuring point amount in two system overlapping regions Survey change curve:First next cycle measuring section is predicted according to each measuring point historical metrology of EMS1 overlay region, further according to each The up-to-date historical metrology value of measuring point and predictive value, make each measuring point in the approximate two system overlapping regions of straight line and measure change curve, obtain Slope, remembers that straight slope required by certain measuring point X is K1.
When predicting next cycle measuring section according to master subsystem historical metrology, the present invention has used for reference winters model, refers to Number smoothing techniques, several ultra-short term bus load Forecasting Methodology such as linear extrapolation, gray forecast approach, Load Derivation, respectively Its different weight of distribution that predicts the outcome, comprehensive above several method is predicted.
B) utilize overlay region historical metrology section in EMS1, ask each measuring point in two system overlapping regions to measure change curve.Root According to each measuring point of master subsystem overlay region up-to-date moment and a upper moment measuring value, make the approximate two system overlapping regions of straight line and respectively survey Point measures change curve, obtains slope, and straight slope required by note measuring point X is K2.
C) estimate section time difference Δ T12.Using master subsystem historical metrology section, make the first regression straight line y1, obtain calculating The each measuring point in moment main system overlay region measures the vertical coordinate of projection on the first regression straight line, and it is vertical that note measuring point X measuring value projects Coordinate is S1Y.Using from subsystem historical metrology section, make the second regression straight line y2, obtain the calculating moment from subsystem overlay region Each measuring point measures the vertical coordinate of projection on the second regression straight line, and the vertical coordinate of the measuring value projection of note measuring point X is S2Y.For weight Each of folded area measuring point, can measure variation tendency according to it, and S1Y, S2YSize come to determine master subsystem initiate calculate Moment is located interval, so that it is determined that each measuring point in overlay region measurement change curve slope is required in should be b).Further each measuring point Time difference Δ t in two systemsi.Worth Δ T is averaging to the measurement time difference of all measuring points in overlay region12=24.6089 seconds.
2) correction portion
EMS1 is by the section estimated out time difference Δ T12It is sent to EMS2 within=24.6089 seconds.
A) EMS2 historical metrology is utilized to predict new measuring section, each measuring point of matching system 2 measures change curve:Estimate and ask Obtain Δ T12=24.6089>0, master subsystem 1 sampling is ahead of from subsystem 2, now predicts new measuring section;Using 3 history Measuring point measuring value in the new section of measuring section and prediction, measures change curve, root with newton each measuring point of differential technique matching Obtain each measuring point according to the section time difference and repair rear measuring value.
According to prediction correction principle, the measuring value of the overlapping region D of subsystem 2 should be with benchmark system (boss after being corrected System 1) overlay region D collection real time data consistent, distributions estimate the measurement using each system Intranet after being corrected Information is carried out.The table that Fig. 7 is given is example error analyses table.This table be the overlapping region D of subsystem 2 is corrected after measure with Subsystem 1 overlay region D measures and is contrasted, and is 7 measuring points taking at random in measuring section in table.Fig. 8 is by measuring point in form Error is expressed as broken line, can apparent find out, the D area of the subsystem 2 after estimating-correcting measures and the D calculating moment subsystem 1 Area's measuring value is more closely, algorithm is more accurate.In Fig. 8, dotted line is relative error before adjustment, and solid line misses relatively for before adjustment Difference.
The above, the only present invention preferably specific embodiment, but protection scope of the present invention is not limited thereto, Any those familiar with the art the invention discloses technical scope in, the change or replacement that can readily occur in, All should be included within the scope of the present invention.Therefore, protection scope of the present invention should be with scope of the claims It is defined.

Claims (9)

1. a kind of measure sampling error modification method with the outer net of correcting algorithm based on estimating, it is characterized in that methods described includes:
Step 1:After distributions are estimated to calculate and are started, master subsystem and obtaining respectively for calculating measuring section from subsystem The parameter of the time difference;
Described master subsystem is the subsystem initiating to calculate;
Step 2:From subsystem, being used for of obtaining is calculated the parameter of the measuring section time difference and send to master subsystem;
Step 3:Master subsystem calculates the measuring section time difference and sends the described measuring section time difference to from subsystem;
Step 4:From subsystem, the measuring value of each measuring point is revised according to the measuring section time difference;
Described master subsystem obtains and includes for the parameter calculating the measuring section time difference:The overlap that master subsystem stores according to itself The historical metrology section in region, extracts the measuring value of the nearest a cycle of each measuring point, is designated as the first measuring value Si,1;Ask for each survey Point first measures the slope K of change near lineari,1, each measuring point second measure the slope K of change near lineari,2Exist with each measuring point Projection vertical coordinate S on first regression straight linei,1Y
Wherein, i=1,2 ..., n, n are the measuring point number of overlapping region.
2. method according to claim 1, it is characterized in that described in ask for each measuring point first and measure the oblique of change near linear Rate Ki,1Including following sub-step:
Sub-step A1:Master subsystem extracts each measuring point nearest p week from the historical metrology section of the overlapping region that itself stores The measuring value of phase;Wherein, p is setting value;
Sub-step A2:Measuring value using each measuring point nearest p cycle predicts the measuring value of each measuring point next cycle;
Sub-step A3:Measuring value phase by the measuring value of nearest for each measuring point a cycle and each measuring point next cycle of prediction Even, obtain each measuring point first and measure change near linear;
Sub-step A4:Calculate the slope K that each measuring point first measures change near lineari,1.
3. method according to claim 1, it is characterized in that described in ask for each measuring point second and measure the oblique of change near linear Rate Ki,2Including following sub-step:
Sub-step B1:Master subsystem extracts each measuring point nearest 2 week from the historical metrology section of the overlapping region that itself stores The measuring value of phase;
Sub-step B2:The measuring value in nearest for each measuring point 2 cycles is connected, obtains each measuring point second and measure change near linear;
Sub-step B3:Calculate the slope K that each measuring point second measures change near lineari,2.
4. method according to claim 1, it is characterized in that described in ask for projection on the first regression straight line for each measuring point indulge Coordinate Si,1YIncluding following sub-step:
Sub-step C1:The each measuring point of the historical metrology profile extraction nearest p cycle of the overlapping region that master subsystem stores from itself Measuring value;Wherein, p is setting value;
Sub-step C2:According to the measuring value in each measuring point nearest p cycle, calculate the first regression straight line of each measuring point;
Sub-step C3:The measuring value of nearest for each measuring point a cycle is projected on the first regression straight line of this measuring point;
Sub-step C4:Calculate the vertical coordinate S of subpointi,1Y.
5. the method according to any one claim in claim 1-4, is characterized in that described acquisition from subsystem is used Include in the parameter calculating the measuring section time difference, the historical metrology section of the overlapping region being stored according to itself from subsystem, carry Take the measuring value of the nearest a cycle of each measuring point, be designated as the second measuring value Si,2;Ask for throwing on the second regression straight line for each measuring point Shadow vertical coordinate Si,2Y
Wherein, i=1,2 ..., n, n are the measuring point number of overlapping region.
6. method according to claim 5, it is characterized in that described in ask for projection on the second regression straight line for each measuring point indulge Coordinate Si,2YIncluding following sub-step:
Sub-step D1:Extract the measuring value in each measuring point nearest p cycle the historical metrology section of overlapping region from subsystem;Its In, p is setting value;
Sub-step D2:According to the measuring value in each measuring point nearest p cycle extracted, calculate the second regression straight line of each measuring point;
Sub-step D3:The measuring value of nearest for each measuring point a cycle is projected on the second regression straight line of this measuring point;
Sub-step D4:Calculate the vertical coordinate S of subpointi,2Y.
7. method according to claim 6, is characterized in that the described calculating measuring section time difference specifically includes following sub-step:
Sub-step E1:Make i=1, N1=0, N2=0;
Sub-step E2:When measuring point i meets Ki,2> 0 and Si,2Y<Si,1Y, or Ki,2<0 and Si,2Y> Si,1YWhen, then make N1=N1+1;
When measuring point i meets Ki,2<0 and Si,2Y<Si,1Y, or Ki,2> 0 and Si,2Y> Si,1YWhen, then make N2=N2+1;
Sub-step E3:If i=n, execute sub-step E4;Otherwise, make i=i+1, return sub-step E2;
Sub-step E4:If N1≥N2, then according to formula Δ tj=(Sj,1-Sj,2)/Kj,2Calculate the time difference of measuring point j;If N1<N2, Then according to formula Δ tj=(Sj,1-Sj,2)/Kj,1Calculate the time difference of measuring point j;
Wherein, j=1,2 ..., n, n are the measuring point number of overlapping region.
8. method according to claim 7, is characterized in that the computing formula of the described measuring section time difference is Wherein, n is the measuring point number of overlapping region.
9. method according to claim 8, is characterized in that described step 4 includes following sub-step:
Sub-step F1:From subsystem, change curve is measured according to each measuring point of subsystem historical metrology cross section correct, specially:
As Δ T12When >=0, utilize the measuring value in each measuring point of historical metrology profile extraction nearest q cycle from subsystem, according to carrying The measuring value that takes predicts the measuring value of each measuring point next cycle, the measuring value further according to each measuring point nearest q-1 cycle and in advance The measuring value of each measuring point next cycle surveyed, matching obtains each measuring point and measures change curve f (t);
As Δ T12<When 0, utilize the measuring value in each measuring point of historical metrology profile extraction nearest q cycle from subsystem, according to each survey The measuring value in point nearest q cycle, matching obtains each measuring point and measures change curve f (t);
Wherein, q is setting value, and t is to measure the moment;
Sub-step F2:Using formulaRevise the measuring value from subsystem each measuring point i;
For revise after from the measuring section of subsystem measuring point i measuring value;
I=1,2 ..., m, m are the measuring point number of the measuring section from subsystem.
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